The invention relates to a sieve device for separating a mixture of particulate material in components of different sizes, comprising a perforated sieve surface that rotates around a central, vertical shaft, said shieve surface having the shape of a hollow, truncated cone casing with a downwardly directed top, on which an imperforate distributor cone with an upwardly directed top has been mounted in the middle, of which distributor cone the base connects to the sieve surface, whereas the supply of the mixture to be separated takes place via a central supply tube placed above the distributor cone, whereas the removal of the coarse component takes place near the circumference of the sieve surface.
A sieve device of this type is known from the Netherlands patent specification No. 7605572 laid open to public inspection. Although this device has a fast, good and dependable operation, and is especially adapted for the separation of coarse press pellets of animal fodder from the grits that have formed therefrom, the size of the passage openings of the sieve surface is constant, whereby the processing of press pellets of different sizes on the same sieve device is impossible.